This invention relates generally to methods and apparatus for interconnecting optical and opto-electronic devices which involve the transmission of light rather than electronic signals.
In the last few years a few fiber-optic systems have transitioned into production. Two examples are the fiber-optic gyro (FOG) and the fiber-optic amplifier. These systems are composed of many-fiber optic and fiber-pigtailed components which must be locally assembled into a continuous optical circuit for these products to function. The assembly process of choice is fusion splicing. Fusion splicing provides an optically low loss and mechanically secure process for connecting fiber ends together to form a continuous optical path. Fusion splicing has been successfully adopted by industry as evidenced by the fact that the United States fiber-optic telephone system is connected exclusively by fusion splices.
Today, fusion splices are performed semi-manually. The fiber ends are mechanically stripped of their jackets, mechano-chemically cleaned, mechanically cleaved, manually inserted into the fusion splicer which automatically makes the splice, manually removed and manually rejacketed and reinforced, and finally the splice and its associated service loops (required to perform the above operations) are manually stored in an appropriate holder. While this semi-manual approach was cost effective for assembling the telephone system, it is not cost effective for manufacturing thousands of fiber-optic systems per year. This has been recognized by the government, and manufacturing technology programs have been started which seek to improve yield by reducing process variability and by automating the entire fusion splicing process except for the storage of the finished splice. When these programs are successfully completed, a cost effective fusion splicing process for assembling these fiber-optic systems will be available to industry.
The automatic fusion splicing process will still be a point-to-point, serial process. The achievement of further cost improvements in the assembly of fiber systems will require a new paradigm. What is needed is a parallel process which can interconnect many of the fibers in a fiber system at once, which does not require the storage of the finished connection, and which does not need service loops thus eliminating the manual operation of storing them. This process would be repeated at most a few times to assemble the entire fiber-optic system, both optically and mechanically.